@Component

public class ApplicationStartupRunner implements CommandLineRunner {

    protected final Log logger = LogFactory.getLog(getClass());

    @Override

    public void run(String... args) throws Exception {

        logger.info("ApplicationStartupRunner run method Started !!");

    }

}

// Simple example

​

@Component

public class MyCommandLineRunner implements CommandLineRunner {

​

    private static final Logger logger = LoggerFactory.getLogger(MyCommandLineRunner.class);

​

    @Override

    public void run(String... args) throws Exception {

        logger.info("This is a sample log message from CommandLineRunner.");

    }

}

​

// Example : Bring data

​

@Component

public class CLRunner implements CommandLineRunner {

​

  @Autowired

  private final RoomReservationService roomReservationService;

  @Autowired

  private final RoomRepository roomRepository;

​

// No need for constructor if @Autowired is used

//  public CLRunner(RoomRepository roomRepository) { 

//    this.roomRepository = roomRepository;

//  }

​

  @Override

  public void run(String... args) throws Exception {

    // Testing by printing table repository data

    List<Room> rooms = roomRepository.findAll();

    rooms.forEach(System.out::println);

    // Testing by printing service output

    SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");

    Date reservationDate = dateFormat.parse("2022-02-14");

    List<RoomReservation> roomReservations = roomReservationService.getReservationsByDate(reservationDate);

    // Display the room reservations in the console

    System.out.println("Room reservations for " + dateFormat.format(reservationDate) + ":");

    for (RoomReservation roomReservation : roomReservations) {

       System.out.println("Reservation ID: " + roomReservation.getReservationId());

       System.out.println("Room Number: " + roomReservation.getRoomNumber());

       System.out.println("Guest Name: " + roomReservation.getGuestName());

       System.out.println("Reservation Date: " + dateFormat.format(roomReservation.getReservationDate()));

       System.out.println("-------------------------");

     }

   }

}